Increased miniaturization of components, greater packaging density of integrated circuits (“ICs”), higher performance, and lower cost are ongoing goals of the computer industry. Semiconductor package structures continue to advance toward miniaturization, to increase the density of the components that are packaged therein while decreasing the sizes of the products that are made therefrom. This is in response to continually increasing demands on information and communication products for ever-reduced sizes, thicknesses, and costs, along with ever-increasing performance.
These increasing requirements for miniaturization are particularly noteworthy, for example, in portable information and communication devices such as cellular phones, hands-free cellular phone headsets, personal data assistants (“PDA's”), camcorders, notebook computers, and so forth. All of these devices continue to be made smaller and thinner to improve their portability. Accordingly, large-scale IC (“LSI”) packages that are incorporated into these devices are required to be made smaller and thinner. The package configurations that house and protect LSI require them to be made smaller and thinner as well.
Many conventional semiconductor (or “chip”) packages are of the type where a semiconductor die is molded into a package with a resin, such as an epoxy molding compound. The packages have a lead frame whose leads are projected from the package body, to provide a path for signal transfer between the die and external devices. Other conventional package configurations have contact terminals or pads formed directly on the surface of the package. Such a conventional semiconductor package is fabricated through the following processes: a die-bonding process (mounting the semiconductor die onto the paddle of a lead frame), a wire-bonding process (electrically connecting the semiconductor die on the paddle to inner leads using lead frame wires), a molding process (encapsulating a predetermined portion of the assembly, containing the die, inner leads and lead frame wires, with an epoxy resin to form a package body), and a trimming process (completing each assembly as individual, independent packages).
The semiconductor packages, thus manufactured, are then mounted by matching and soldering the external leads or contact pads thereof to a matching pattern on a circuit board, to thereby enable power and signal input/output (“I/O”) operations between the semiconductor devices in the packages and the circuit board.
In response to the demands for miniaturization, the distance between the semiconductor chips are decreased to achieve higher density thereof in order to mounting the high frequency LSI adjacent to other high frequency LSIs. This practice has led to problems of LSI being increasingly affected by noise, more specifically electromagnetic interference (EMI).
Conventionally, a technique for addressing the EMI problem is covering a package of a semiconductor device with a metal package structure. However this metal package structure generally has to be mounted on the printed circuit board as an independent component separated from the semiconductor device, and thus the size of package with the metal package structure increases, thereby prohibiting or limiting the miniaturization of the package. In addition, the metal package structure is formed as a component separated from the semiconductor device, thereby increasing manufacturing cost.
Numerous package approaches attempt to provide shields within the semiconductor packages. However, this requires custom structures taking into account the integrated circuit size, height, and any stacking configurations as well as other elements in the package, such as bond wires or other devices. Also, customization is required to attach the shields to the appropriate ground source. All these considerations, as well as others, increase the complexity of the manufacturing process, decreases yield, and increased cost.
Thus, a need still remains for an integrated circuit package system providing low cost manufacturing, improved yields, reduction of integrated circuit package dimensions, and solving the problems caused by noises. In view of the ever-increasing need to save costs and improve efficiencies, it is more and more critical that answers be found to these problems.
Solutions to these problems have been long sought but prior developments have not taught or suggested any solutions and, thus, solutions to these problems have long eluded those skilled in the art.